The purpose of a trademark is to distinguish or identify the source of a good or service that is used in commerce. Thus, trademark law aims at avoiding consumer confusion with regards to the source of a product or service, and as such, the examining attorney will issue a likelihood of confusion refusal if he or she determines that the proposed trademark would likely cause confusion with an existing trademark. When the examining attorney reviews a federal trademark application, he or she must only consider the facts of the application and ignore prior trademark rulings.
Trademark law states that no one factor will be determinative of whether consumers would likely confuse one trademark for another. All of the factors are looked at as a whole. In some circumstances, some factors may be given more or less weight than others. The Trademark Trial and Appeal Board follows what are known as the “du Pont” factors when analyzing likelihood of confusion.